[Rd] change in behavior of <<-

[Vincent Carey 525-2265]

There has been a change to the behavior of <<-.
See the error thrown at the bottom of the transcript
below.  I don't believe this is an intended change.

==========
older version of R-devel
==========

> version
         _
platform i686-pc-linux-gnu
arch     i686
os       linux-gnu
system   i686, linux-gnu
status   alpha
major    1
minor    9.0
year     2004
month    03
day      09
language R
> x <<- list()
> x[["a"]] <<- list()
> x[["a"]][["b"]] <<- 3
> x
$a
$a$b
[1] 3

===========
more recent version of R-devel:
===========

> version
         _
platform i686-pc-linux-gnu
arch     i686
os       linux-gnu
system   i686, linux-gnu
status   beta
major    1
minor    9.0
year     2004
month    03
day      30
language R
> x <<- list()
> x
list()
> x[["a"]] <- list()
> x
$a
list()

> x[["a"]] <- 2
> x
$a
[1] 2

> x[["a"]] <<- 2
Error: Object "x" not found